Cable Consstruction

The HELIX IMAGE (Air)

NOTE: This page ONLY describes the process of insulating the Signal or Live wires of the Helix IMAGE cables.
  • strange as it may seem, you DO NOT have to apply this insulation guide to the Neutral wire

Links to the pages on how to build the individual cables can be found at the bottom this page


So How do you build a conductor that has Air as the dielectric?

Teflon tube has been a long time favourite in my cables (early on) so I looked back a previous versions of the cables and realized if I used the right sized tube it would allow enough air around the wire and result in a very small area of contact.

I selected a PTFE Tubing with Internal Dia = 0.106" and Outside Dia = 0.130" - from Take Five Audio

This tube can be used for either
  • a single 14/12 gauge wire when used to fabricate the Signal or Live wires for the speaker cables and power cables
  • or the 2 x 18 gauge (for Interconnects) and the 2 x 16 gauge (for SOURCE power cables)
  • so basically, this teflon tube it is suitable for all Interconnect, speaker and mains cables

Looking at the diagram below, of the cross section of a Live conductor of a mains cable and a twisted pair signal conductor of the interconnect cable it is quite clear that provided the tube does not collapse there is only ever ONE point of contact with the teflon tube, with lots of air around the actual wire

This is the value Teflon has over Cotton and Silk sleeves, because cotton and silk tend to collapse around the wire resulting in multiple points of contact, increasing the value of the Dk



00 cross section


Unfortunately, the UP-OCC copper I have been using from both Neotech and VH Audio both have insulation that must first be removed, but bare UP-OCC wire can be purchased from retailers such as Part Connexion

In order to remove the insulation with a minimum of effort I inserted an eye ring in the end of a piece of wood (see below) to make a simple striping jig

  • Thread the wire through the eye ring
  • hold the wire on the board at the other end of the board
  • Place the blade of a utility knife on the wire and lift the blade to about a 5 degree angle
  • and simply cut a small sliver of insulation from the wire
  • then peel the insulation from the wire


01 board

The rest of this process depicts how to fabricate the Signal conductor for the Helix interconnect
  • which uses 2 x 18 gauge wires
  • but the same process can be applied to any HELIX IMAGE (Air) Cable



FOR the 2 x 18 gauge Interconnect SIGNAL CONDUCTOR
AND the 2 x 16 gauge Source Power Cables LIVE CONDUCTOR


Strip the insulation from the two wires (as shown above) and twist one end tightly to hold the wires together

02 twist tight

Then twist the two wires together at the rate of about one complete twist every 3-4 inches

And twist the last 1/2" or (centimetre) to prevent the wires from untwisting, as below


03 twist loose

Then insert the tightly twisted portion into a drill chuck and hold the other end with a pair of pliers

04 drill

Rotate the drill clockwise i.e. clockwise as you look down the wire from the rear of the drill

Rotate until the wire is evenly twisted - approximately 3 twists per inch - as below


05 Drill Twist

Remove the wire from the drill chuck - it will remain twisted, but tightly twist the end to match the the opposite end

Then "TIN" the wire with solder for about 1" at each end - this prevents oxidation outside the Teflon tube


06 tin ends

Insert the wire into the teflon sleeve and apply a small piece of heat shrink tubing that has the adhesive on the inside

An optional alternative is to seal the ends with hot glue

This seals the tube and prevents air flow and prevent oxidation of the bare wire


07 seal ends

FOR the 2 x 16 gauge Speaker Cable SIGNAL CONDUCTOR
AND the 2 x 14 gauge (heavy duty) HD Power Cables LIVE CONDUCTOR


A similar process is required, except that each of the two wires is inserted into it's own tube and then gently twisted as shown below
i.e. approximately 1 complete twist every 4" (10cm)

Speaker-Live


The Power Cable LIVE conductor is terminated with a spade and both tubes are sealed with a single piece of Heat Shrink as show below.
Only attach the speed at one end to allow for easy insertion into the Helix Coil and then attach the other spade



Power term

Using this technique, a view of a cross section of the twisted pair conductor reveals…


Twisted Pair X


This provides an additional benefit when the twisted pair conductor is placed inside the Helix Coil of the speaker cables





No Beads

If desired the conductor assembly can be placed inside a cotton sleeve for improved vibration control, but it is NOT required


So why prevent air flow?
  • In order to prevent the bare copper wire (or silver) from oxidizing
  • Initially some oxidation will occur and a little dullness will result
  • but based on my current speaker cables which have been in place for about 4 months, the dulling of the copper appears to have stopped

I was initially very concerned about oxidation because if it was a real issue it meant people would be faced with re-wiring their cables once they turn green.
  • But on thinking about the oxidation process further, those copper weather veins on buildings generally take about 5 - 7 years to obtain the green patina
  • they are open to the elements 24/7.
  • Also, the bare ground wire in my house (that connects to the water supply) is still pretty bright after 4 years
I believe sealing the wire inside a Teflon tube using the approach above will protect the wire from oxidation for a considerable period of time. i.e. many years

In recognition of the superb performance achieved by applying this technique I have decided to name this versos of the HELIX cables…

The HELIX IMAGE (Air)


When this approach is used on all Helix cables the results are stunning !!!


So In Summary

  • Interconnect Cable Signal Wire is 2 x 18 gauge UP-OCC twisted wire inside a single Teflon Tube
  • Speaker Cable Signal wire can be either 2 x 16 gauge or 2 x 14 gauge, where each wire is in it's own Teflon tube with a gentle twist
  • Source Power Cable Live wire is 2 x 16 gauge twisted wire inside a single Teflon Tube (see warning below)
  • HD Power Cable is 2 x 14 gauge Live wire where each wire is in it's own Teflon tube with a gentle twist
  • The neutral and ground wires are unchanged from the original design

WARNING: You may be tempted to use a single tube on the speaker cables if using 2 x 16 gauge wire, but it becomes increasingly more difficult to insert the twisted conductor into the tube after about 4-5 feet

This technique can be applied to any of the following HELIX IMAGE Cables…
Interconnect Cable...
USB Cable...
Speaker Cable...
Power Cable...